| dc.creator |
Talhavini M. |
|
| dc.creator |
Atvars T. D. Z. |
|
| dc.date |
1998 |
|
| dc.date.accessioned |
2013-05-30T11:02:44Z |
|
| dc.date.available |
2013-05-30T11:02:44Z |
|
| dc.date.issued |
2013-05-30 |
|
| dc.identifier |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40421998000300015 |
|
| dc.identifier |
http://www.doaj.org/doaj?func=openurl&genre=article&issn=01004042&date=1998&volume=21&issue=3&spage=332 |
|
| dc.identifier.uri |
http://koha.mediu.edu.my:8181/jspui/handle/123456789/4352 |
|
| dc.description |
We describe in this work a simple experimental set up to perform time dependent luminescence experiments in time scales from mili-seconds to seconds, based on the phase resolution of the emission signal. This system is composed by modulation of a continuous light source with an external chopper controlled by a lock-in amplifier. We exemplified the utility of the system in studies of phosphorecence emission using benzophenone dissolved in polystyrene and since the phosphorescence intensity and lifetime are temperature-dependent processes, we also studied polymer relaxation processes in the temperature range from 20 to 400K. A software that drives the spectrofluorimeter and controls both the cryosystem and the lock-in amplifier was developed. |
|
| dc.publisher |
Sociedade Brasileira de Química |
|
| dc.source |
Química Nova |
|
| dc.subject |
phase resolution lifetime determinations |
|
| dc.subject |
benzophenone |
|
| dc.subject |
polymer relaxation processes |
|
| dc.title |
Aquisição de tempos de vida de fosforescência com resolução de fase e sua aplicação ao estudo de relaxações em polímeros |
|